H3K9的甲基化调节了通过不连贯的前循环来抑制异性染色素的沉默
Kannosuke Yabe1, Asuka Kamio1, Satoyo Oya1
1Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan.
Science advances
|June 26, 2024
概括
矛盾的是,素H3 lysine-9甲基化 (H3K9me2) 诱导H3K36me3,从而防止沉默. 这种表观遗传交叉声调节了基因沉默和反沉默通路,定义了染色质域.
科学领域:
- 表观遗传学和基因调节
- 植物分子生物学 植物分子生物学
- 染色素的结构和功能.
背景情况:
- 基因组H3 lysine-9甲基化 (H3K9me) 是一个关键的表观遗传标记,与转录无声的异色素有关.
- 通过H3K9me控制基因沉默的精确机制及其域的界限仍然不完全理解.
- 了解这些过程对于解释如何保护重要基因免受沉默至关重要.
研究的目的:
- 为了研究H3K9me2和其他基因基因基因表达调节中的基因基因修饰之间的功能相互作用.
- 阐明细胞如何建立和维持不同的异色和单色域.
- 为了揭示创建表观遗传变异的分子基础.
主要方法:
- 利用Arabidopsis遗传系统在基因和转子体中诱导H3K9me2.
- 研究了H3K36me3的沉积,以应对H3K9me2的积累.
- 研究了甲基转移酶ASHH3在H3K36me3沉积中的作用.
- 评估了H3K36me3对H3K4me1通过LDL2.2去甲基化的影响.
主要成果:
- 矛盾的是,H3K9me2的积累导致了由ASHH3.3介导的Euchromatic标记H3K36me3的沉积.
- 由ASHH3诱导的H3K36me3通过抑制LDL2介导的H3K4me1脱甲基化而产生抗沉声作用.
- 这种相互作用表明,H3K9me2可以调节静音和反静音通路.
结论:
- H3K9me2通过协调对立的表观遗传路径,积极协调基因沉默.
- 在H3K9me2介导的静音和H3K36me3介导的抗静音之间的平衡对于正确的染色体域分区至关重要.
- 这些发现提供了关于表观遗传机制产生转移稳定的表观遗传变异的见解.
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